Markup languages have been used by content providers to structure and presenting content for the World Wide Web. Some of these languages (such as HTML5) aim to improve the language with support for the latest multimedia while keeping the language easily readable by humans and consistently understood by computers and devices. Some of the other languages (such as CSS) aim to create visually engaging webpages and user interfaces while separating the document content from the document presentation. However, these markup languages are not immune from device and OS fragmentation, i.e., a content presentation written in these languages are not consistently understood by different computers and devices. In order to create an engaging webpage, its author must have sufficient knowledge of his target device and carefully craft the presentation based on the peculiar capabilities of his target device.